Merge pull request #15 from nitmir/dev

Update version to 0.7.3

Added
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* Add autofocus to the username input on the login page

Fixed
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* Really pick the last version on Pypi for new version checking.
  We were only sorting version string lexicographically and it would have break when
  we reach version 0.10.N or 0.N.10
* Only check for valid username/password if username and password POST fields are posted.
  This fix a bug where posting without it raise a exception are None where passed for
  username/password verification.